Conventionally, there are capacitance touch panels mounted on display screens of display apparatuses as conventional position input apparatuses for detecting positions at which capacitance values distributed in a matrix are changed. This touch panel is, for example, a conventional capacitance detection apparatus for detecting a distribution of capacitance values of a capacitance matrix formed in between an M number of drive lines DL and an L number of orthogonal sense lines SL.
In the touch panel of the conventional capacitance detection apparatus, when a finger or a touch pen contacts or comes close to the touch panel surface, the capacitance value of the position where the finger or touch pen contacts or comes close changes. By utilizing this phenomenon, the position at which the capacitance value is changed is detected to detect the position where the finger or touch pen has touched as coordinates.
A touch pen for a capacitance touch panel, in which a conductive material having the same characteristic as a finger is used on a predetermined portion of a tip of the pen, is disclosed in Patent Document 1.
FIG. 36 is a side view of a case that an input to the touch panel is made using the conventional touch pen disclosed in Patent Document 1.
In FIG. 36, with regard to the conventional touch panel system, detection is made with capacitance data from a touch panel 102, in which a tip section 101 of a touch pen 100 is allowed to contact the touch panel 102 and in which the three-dimensional coordinates (x1, y1, z1) of a tip point P1 of a conductive section 103 away from the touch panel 102 by a certain distance z1 are used as a pen input. The three-dimensional coordinates (x1, y1, z1) are such that the x and y coordinates are determined on the surface of the touch panel 102 and the z coordinate is determined in the vertical direction from the touch panel 102 to determine the three-dimensional coordinates (x1, y1, z1).
FIG. 37 is a side view showing a state where a tip section 101 of a conventional touch pen 100 in FIG. 36 is biased by a spring.
As shown in FIG. 37, the non-conductive tip section 101 of the conventional touch pen 100 is biased outwardly by a spring 104 within a conductive section 103. The non-conductive tip section 101 is capable of retracting into or protruding from the conductive section 103, which is consecutive from the non-conductive tip section 101, in accordance with pen pressure, to change the pen pressure in accordance with a detected height z (distance z) of the conductive section 103. The detected height z (distance z) of the conductive section 103 can be used by an application processing section 206 to be discussed below, as pen pressure information. The application processing section 206 is capable of making the handwriting of a handwritten letter bolder or capable of making the shade of the handwritten letter darker in an application to be discussed below, as the detected height z (distance z) of the conductive section 103 is shorter.
FIG. 38 is a functional block diagram of a conventional information terminal apparatus with which a conventional touch pen 100 and touch panel 102 of FIG. 36 are used.
In FIG. 38, a conventional information terminal apparatus 200 comprises: a capacitance touch panel 102; a sensor information obtaining section 201 for obtaining output information from the touch panel 102; a height computing section 202 for eliciting a distance z1 (height coordinate) from the touch panel 102 to the conductive section 103 of the touch pen 100 as height information, based on sensor information obtained by the sensor information obtaining section 201; a pen pressure converting section 203 for converting the height information into a pen pressure value; a coordinate calculating section 204 for eliciting XY coordinate values on the touch panel 102 of the conductive section 103 based on the sensor information; a coordinate correction section 205 for correcting the calculated XY coordinate values so that the values are adjusted to the position of the pen tip; an input information notifying section 205 for notifying the pen pressure information and XY coordinate information of the pen tip to an application processing section 206; and the application processing section 206 for performing processing, such as handwriting drawing, in accordance with the pen pressure based on an output from the input information notifying section 205.
According to the configuration described above, first, the sensor information obtaining section 201 obtains the three-dimensional coordinates (x1, y1, z1) of a tip point P1 of the conductive section 103 of the touch pen 100 as sensor information; and first, the coordinate calculating section 204 elicits the XY coordinate values on the touch panel 102 of the conductive section 103 based on the sensor information, and then the coordinate correction section 205 corrects the calculated XY coordinate values so that the values are adjusted to the position of the pen tip. In addition, the height calculating section 202 elicits height information (distance z1) based on the three-dimensional coordinates (x1, y1, z1) of the sensor information obtained by the sensor information obtaining section 201, and the pen pressure converting section 203 converts the height information (distance z1) into a pen pressure value.
Next, the application processing section 206 performs drawing display processing on handwriting drawing to make the shade of a handwritten letter darker in accordance with the pen pressure, based on XY coordinate information and pen pressure information from the input information notifying section 205.